Implantable active medical devices, such as cardiac rhythm management devices (pacemakers and defibrillators) and a variety of implantable muscle/nerve stimulators, for example, generally include a battery and battery-powered electronic pulse generator contained within a hermetically sealed housing or case and attached to a lead connector housing or block. The lead connector block is often affixed to the hermetically sealed housing with brackets, metal solder, and/or a medical grade adhesive. The connector housing contains components that electrically connects a therapy lead to the pulse generator electronics.
The electronics within the hermetically sealed housing are conductively coupled to the lead connector block with an electrical feedthrough assembly. Electrical feedthroughs serve the purpose of providing a conductive path extending between the interior of a hermetically sealed container and a point outside the hermetically sealed housing. The conductive path through the feedthrough usually includes a conductor pin or terminal that is electrically insulated from the hermetically sealed housing. While this arrangement has proven to be highly reliable, it involves a variety of expensive manufacturing processes and parts that necessarily increase the cost and overall volume of the resulting product.
In many implantable active medical devices in industry, the device housing (also known as shields) provide the structure to which internal components are fixed. Most often the shields are made of thin metallic material and therefore the major surfaces can be somewhat flexible. Components may be fixed to the flexible surfaces by means such as epoxy or pressure sensitive adhesive resulting in relative movement between the internal components. Strain relief for electrical or mechanical interconnects between components is required to improve device lifetime.
Ongoing efforts by the industry to reduce the size of the implantable device are desired. Early implantable pacemakers back in the 1960's were about the size of a hockey puck. With advances in microelectronics and integrated circuitry, significantly more features and capabilities have been embodied in implantable active medical devices that can be very small. Nonetheless, efforts to further reduce the size of implantable active medical devices continue in the industry.